When I first started running, this is how I built myself up.
I started small: just 3 minutes a day, 3 days a week. Then moved up to 5 minutes, then 7, and kept slowly adding time from there. It took several months, but eventually I could run 45 minutes at a time, and it actually felt easy.
I’ve thought about doing more, but I’ve also seen a lot of long-term runners end up with bad knees. So I’ve usually kept myself around the 45-minute mark, about 2 or 3 days a week. For me, that feels like a good balance between staying in shape and not overdoing it.
But I do it on a treadmill so safer. Way more boring though, but safer. lol